Cl[C:2]1[CH:3]=[CH:4][C:5]2[C:9]([OH:10])=[C:8]([C:11]#[N:12])[O:7][C:6]=2[CH:13]=1.[CH3:14][NH:15][NH2:16]>C1C=CC=CC=1>[CH3:14][NH:15][NH:16][C:11]([C:8]1[O:7][C:6]2[CH:13]=[CH:2][CH:3]=[CH:4][C:5]=2[C:9]=1[OH:10])=[NH:12]3-Hydroxybenzo[b]furo-2-carbonitrile (1.40 g, 8.8 mmol, described in Example 3) was dissolved with heating in benzene (50 mL) and methyl hydrazine (1 mL, ca. 19 mmol) was added. The solution was stirred and refluxed for 2 hr and evaporated to dryness. The pasty residue (ca. 2 g) was applied in chloroform solution to chromatography on neutral alumina. Elution with 2% MeOH in CHCl3 (v/v) gave 3-hydroxybenzo[b]furan-2-carboximidic acid, 2-methylhydrazide (0.79 g): IR (CHCl3) 3510, 3480, 3450, 3200, 1635 and 1595 cm-1 ; and NMR (CDCl3) δ2.65 (3H, s), 5.7 (3H, broad), ca. 7.4 (1H, br), 7.2 (3H, m) and 7.75 (1H, d).
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